October 20, 2003.
By MURRAY EVANS,
The Associated Press State & Local Wire.

LEXINGTON, Ky.

A University of Kentucky researcher announced Monday what is touted as a breakthrough in the study of age-related macular degeneration, an eye condition that affects millions of older Americans.

Jayakrishna Ambati, an assistant professor of ophthalmology and director of ophthalmic research at the university's College of Medicine, said his research team has identified the first animal model - genetically modified mice - that reproduces virtually all the important features of human macular degeneration.

At present, there are no treatments to preserve or improve vision for those who have macular degeneration. Ambati said the absence of an animal model for research purposes has hindered the development of possible treatments.

"These mice offer the ability to understand the mechanisms leading to all stages of macular degeneration and a platform for developing and testing new drugs for this condition," Ambati said.

"Vision is the sense that most people dread losing and macular degeneration is a principle thief of this most valuable gift. We are excited about the prospect that these mice provide an unparalleled opportunity to unravel the mysteries of this blinding condition.

"This is a crucial and critical first step."

Macular degeneration, which affects the central part of the retina, usually develops after a person reaches 50 and is the leading cause of blindness in the United States, Ambati said. About one-third of people older than 75 have the disease.

Barrett Rollins, an associate professor of medicine at Harvard Medical School, said he was conducting a study on a separate medical condition when Ambati asked him about the mice used in Rollins' research. Rollins supplied the genetically modified mice for Ambati's study.

"This is one of the examples of how science in the 21st century is done," Rollins said. "People very freely exchange research tools. There is a free flow."

Ambati said research is ongoing at UK to determine possible treatments for the disease. Gene-therapy and drug experiments are being conducted toward that goal, he said.

"If those experiments prove fruitful, it would be logical to progress on to see if those kinds of drugs may have value in (human) patients," he said.

He said it would be at least two to three years before any human trials could begin.

Ambati's research will be published in the November edition of Nature Medicine.